The typical work station in a home or business includes a phone, a fax modem, and a computer, all connected to one another and to the central office. FIG. 1 is a block diagram of the typical work station according to the prior art including a computer 12 connected to a modem 11. The modem 11 includes an interface 14 between the computer 12 and a controller 16. The modem 11 also has a data processor 18 which communicates with speaker 20, microphone 22, telephone 24 under control of controller 16 according to the program stored in memory 26. The modem 11 also includes a current generator 28 for operating the speaker 20 and microphone 22. The modem 11 is connected to the central telephone office 30 through the DAA (data access aitangement). The circuitry of the sections shown in FIG. 1 is well known to those having ordinary skill in the art.
U.S. Pat. No. 5,506,891 to Brown discloses a method and apparatus for detecting the connection status of an extension phone connected to a voice/fax modem. Off hook condition is indicated by a comparison of an average line voltage to an instantaneous voltage. The modem responds to the detection of off-hook extension line by deactivating a voice answering machine cycle.
U.S. Pat. No. 5,610,920 discloses coupling of voice and computer resources over LAN networks.
U.S. Pat. No. 5,699,413 discloses a system for ;simultaneously enabling a voice and data session by detecting differences in the sessions and directing each session to an appropriate channel.
None of these disclosure consider problems of communication between two members of a local area network (LAN) that are addressed by the present invention.
In both homes and in business offices, more than one work station is being installed at separate location in the home or office. The locations of these stations are ideally separate from one another, in separate rooms and even on separate floors, or even separate buildings. For example, in a home, one work station may be in an upstairs bedroom and a second work station may be in the garage. In order for one party to communicate with a second party, he either has to interrupt his work and go to the other site, or he has to shout to the other party to pick up the phone. When the first party does succeed in alerting the other party to pick up the phone, the dial tone is present on the line which is, at best, an annoyance to both parties.